As part of an effort to validate or disprove the diagnosis of prepubertal major depressive disorders, we are studying in children with this disorder psychobiological parameters which are known to be altered in adult major depressive disorders. In this continuation application funds are being requested to continue the study of sleep physiology, circadian rhythms of cortisol, prolactin and growth hormone, growth hormone response to ITT and 24 hour MHPG excretions. Their biological measurements are carried out in 3 groups of prepubertal children: a) a group fitting RDC criteria for major depressive disorder during illness (pretreatment, ill) and on follow up (recovered, off medication), b) a group fitting criteria for nondepressed emotional disorder and c) a group of normal children. We are searching for psychobiological markers of either illness or predisposition specific to depressed children.